Satellite- based drought indicators for supporting sustainable water management

BACKGROUND AND OBJECTIVES: Over the past decades, pressures have placed the basin’s ecological and hydrological systems at serious risk. The Azraq , located in eastern Jordan, is an essential ecosystem reliant on groundwater, which is facing growing threats from extended periods of drought and excessive groundwater extraction. This study aims to provide a comprehensive evaluation of hydrological drought, and demonstrate the value of satellite-based indices as decision-support tools for sustainable water resource management.METHODS: Multi-temporal Landsat satellite imagery from 1990 to 2024 was analyzed to assess spatial and temporal variability in surface moisture conditions. Two remote sensing-based indices, specifically the normalized difference moisture index and the normalized difference water index, were implemented during eight benchmark years. The indices were evaluated for their sensitivity to moisture stress, their effectiveness in identifying hydrological deficits, and their ability to pinpoint persistent drought hotspots related to groundwate.FINDINGS: Both indices revealed a consistent decline in surface moisture, with a marked reduction after 2000 that coincided with major drought periods and rainfall anomalies. Normalized difference moisture index exhibited increased sensitivity to localized surface moisture stress, while also successfully capturing hydrological deficits on a basin-wide scale. Persistent drought hotspots were identified in zones of intensive groundwater abstraction, with the Azraq Oasis exhibiting continuous water scarcity despite its historically water-rich status. While the years 1990, 1995, and 2020 showed localized improvements, 2000 reflected extreme drought conditions and 2020 displayed the highest recovery in surface moisture. Normalized difference moisture index highlighted greater spatial variability in drought severity, whereas both indices consistently demonstrated escalating drought conditions across the basin.CONCLUSION: The results confirm worsening drought trends in the Basin and highlight the importance of satellite-based indices in supporting adaptive water management and policy development. To strengthen resilience, urgent measures are needed, including integrated drought monitoring systems, stricter regulation of groundwater abstraction, and restoration of critical wetland areas. It is recommended to implement complementary strategies such as demand-side management, enforcing limits on water usage, promoting agricultural practices that use water efficiently, and performing regular hydrological assessments. Integrating satellite-based drought monitoring into water governance frameworks can provide robust, science-based guidance for protecting the Azraq Basin against the combined pressures of climate variability and human activity.